This application claims the priority of Korean Patent Application Nos. 2003-31322, filed on May 16, 2003, and 2003-72810, filed on Oct. 18, 2003, in the Korean Intellectual Property Office, the disclosures of which are incorporated herein in their entirety by reference.
1. Field of the Invention
The present invention relates to image encoding and decoding, and more particularly, to an image encoding/decoding method and apparatus using residue prediction of an image.
2. Description of the Related Art
In general, to increase compression ratio, an R-G-B image output from a device is transformed into a Y-Cr-Cb image suitable for compression. However, when the R-G-B image is transformed into the Y-Cr-Cb image, picture quality is damaged. In general, when the Y-Cr-Cb image is compressed, Cr and Cb components are encoded by reducing their magnitudes by 4 times for compression efficiency. Therefore, after the Y-Cr-Cb image is encoded, it is difficult to restore the original image with high quality.
If each of R-G-B components is independently encoded in a conventional Y-Cr-Cb encoder in order to reduce the transform loss of the Y-Cr-Cb image, since correlations among the R-G-B components cannot be used, encoding efficiency drops. A conventional compression method in this respect is presented in the AVC/H.264 standard jointly developed by the ISO/IEC MPEG and ITU-T VCEG groups. A detailed description of this method is disclosed in “Text of ISO/IEC FDIS 14496-10: Information Technology—Coding of audio-visual objects—Part 10: Advanced Video Coding”, ISO/IEC JTC 1/SC 29/WG 11, N5555, March, 2003.